The prevention and, more generally, the anticipation of (risks of) harm are, rightly or wrongly, at the heart of contemporary concerns. For proof of this, we need look no further than the way in which climate, health, biotechnology and terrorist threats to human security are addressed.
The law is no exception to this trend, and has even become one of its driving forces. This is clearly demonstrated by a very specific legal standard:due diligence. This standard or norm of behavior now plays a central role in the qualification of many new obligations to prevent certain risks, and then to protect against their consequences, when the latter are obligations to endeavor and not to guarantee. In certain circumstances, under certain conditions and within certain limits, the law requires us to exercise reasonable diligence, care or vigilance, or conversely, to refrain from harming others by complying with the conduct it prescribes, in order to protect various rights or interests against (risks of) harm, provided that we have foreseen them or should have foreseen them, and that we have the necessary capacity to do so.
Due diligence is an ancient concept, dating back to ancient law, particularly Roman law. It is therefore now a well-established standard of behavior in Western legal tradition, albeit in very varied forms, and has made its way, after various twists and turns, into contemporary international law. For some time now, however, there has been renewed interest in this standard of conduct and in the liability for undue negligence that arises from its violation. This is evident in national law, whether in corporate law (with the duty of care owed by parent companies to their subsidiaries) or environmental law (with risk assessment measures or impact studies). However, this is also, and above all, the case in international law, and particularly in recent international case law. This can be seen in international human rights law, international environmental law (particularly maritime law), international health law, international humanitarian law, international disarmament law and international investment law. And this is, of course, particularly the case in the new regime of international disaster law.
